StraightToolsAge Calculator
Calculate age in years, months, days, and total elapsed days.
Age calculation
Calendar years, months, and days are calculated using the current date in your browser.
When to use this tool
Use the age calculator to turn a birth date into calendar years, months, days, and total elapsed days. It can help with birthdays, age requirements, records, and date checks.
How the result is calculated
Calendar age is calculated from the birth date to the current date, accounting for month lengths and leap years rather than assuming every year contains the same number of days.
Worked example
Someone born exactly ten calendar years ago will show an age of ten years even though the total number of elapsed days depends on how many leap days occurred in that span.
What to keep in mind
Legal age rules can depend on jurisdiction and may define when an age is attained differently for specific purposes. Verify formal eligibility requirements independently.
About our calculations
StraightTools is designed to show the method behind the answer, not just the result. Inputs are handled in your browser for this tool. For important financial, legal, medical, tax, safety, or contractual decisions, verify the result with an appropriate authoritative source or qualified professional.